JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
(16:30:48) Shot opens to Representative FLOYD J. FITHIAN asking witness, Dr. VINCENT P. GUINN, about the composition of a bullet - Guinn gives the percentage of the bullet's lead composition (16:31:07) Fithian wants Guinn to go further in explaining the certainty of the tests he's done to show that the fragments of lead found in Governor JOHN CONNALLY'S wrist match up with the infamous bullet 399, the "pristine bullet" - Guinn can only say that the tests he ran show the fragment and bullet 399 are indistinguishable in their composition, vs. in comparison with the other bullet fragments which they do not match (16:32:41) Guinn: "It is very unlikely" that the bullet fragment is from a bullet other than 399, though it is possible (16:33:17) Fithian asks Guinn to confirm his conclusion that there is no evidence of any other bullets from a compositional diagnosis of the bullet and fragments - Guinn confirms that all fragments match up with two bullets only (16:34:20) Fithian asks Guinn to explain the advantages and differences of and between Neutron Activation Analysis vs. the method of analysis used by the Warren Commission, Emission Spectrographic Method - Guinn responds that activation analysis is much more sensitive in its readings, gives measurements quantitatively versus abstract categories of different levels (e.g. a trace), and does not necessitate the destruction of the sample being analyzed
JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
(16:36:30) Fithian asks about an article published that said Guinn was not reliable for such testimony as he had participated in the Warren Commission - Guinn responds he never worked for or was consulted by the Warren Commission - Guinn then goes on in response to another Fithian question to tell the committee that the Warren Commission did conduct Neutron Activation Analysis tests but that the results of them were not released for a long time (16:38:45) Fithian asks why the test results were not divulged earlier - Guinn responds that he believes it is because the results were inconclusive, the Warren Commission felt no one needed to know this, he reads from a letter issued by J. EDGAR HOOVER which sums up the results as inconclusive (16:41:57) Guinn gives the story of the FBI's utilization of Neutron Activation Analysis for the Warren Commission in 1964, he believes this is the first time they had ever used it (16:43:54) Guinn says that his review of the raw data from the initial activation tests done in '64 was also inconclusive, then he did the tests he is presenting today and they came out very conclusive so he returned to the initial tests data, now looking back after success Guinn was able to figure out how the measurements in the initial test did work out in the same conclusive way
JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
(16:46:55) Fithian asks if Guinn is saying that the 1964 data was actually conclusive - Guinn responds yes, the data was there but the correct interpretation of it was not (16:47:32) Fithian and Guinn have a fairly technical discussion of how the Neutron Activation Analysis test works, charts of gamma ray measurements are incorporated in this (16:50:50) Fithian asks if Guinn did his tests on the same pieces as were used in '64 - Guinn responds no, that those pieces were not at the National Archives and that he does not know where they are - Fithian asks further questions about why they might be lost and again confirms that the data from this original test was in fact conclusive (16:52:43) Fithian says that he's stressing the fact that '64 tests produced conclusive data that was not released to the public because during this time people had leveled the criticism at the Warren Commission that they were not doing the test because the results would prove something other than the single bullet theory - Guinn reiterates that all he knows is that the tests were conducted and at that time they couldn't conduct a proper statistical analysis of the data, which he was able to do after a second round of successful tests (16:55:05) Fithian asks if anywhere in the results or data from the initial tests if there's anything that suggest the fragment found in Connally's wrist was from a bullet other than 399 - Guinn responds no
JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
(16:55:52) Fithian asks if anybody at the FBI could have been able to come to the expert conclusions that Guinn has come to in matching the fragments and bullets without a knowledge of Mannlicher-Carcano ammunition - Guinn responds it would have been much more difficult and goes on to explain the unique characteristics of the composition of this ammunition (16:57:50) Fithian asks if in '64 the FBI could have come to Guinn's conclusions - Guinn responds it would have been hard and explains briefly (16:58:27) Fithian confirms all of Guinn's FBI information came from publicly accessible sources (16:59:40) Fithian asks if there are any other tests Guinn would recommend - Guinn responds no and explains (17:00:45) Fithian confirms that Guinn's findings shed no light on whether or not bullet 399 passed through JFK before Connally - Guinn responds that all his findings conclude is that bullet 399 broke Connally's wrist, as the wrist was the only body part to contain a fragment (17:01:53) Fithian confirms Guinns over all findings, that bullet 399 matches the fragment in Connally's wrist, that a fragment removed from JFK's skull matches the two fragments found in the car and that there is evidence of only two bullets (17:02:39) Committee Chairman LOUIS STOKES ask about the number of Neutron Activation Analysis experts '63 and now - Guinn responds giving a history of the test and stating it was first developed in 1937
JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
(17:04:48) Stokes recognizes Guinn's opportunity to supplement his testimony - Guinn takes this time to undercut his test results by explaining that the composition numbers represented in his report do not match up exactly and that to see that fragments belong to the same bullet one has to take into consideration variability of composition within the bullet itself (17:09:35) Stokes is provoked by Guinn's closing statements to ask if another expert on Neutron Activation Analysis would come to the same conclusions as Guinn - Guinn says yes on close examination (17:10:20) Counsel JIM WOLF puts forth for the record that an independent Neutron Activation specialist has been consulted and he came to the same conclusions with Guinn's data
JFK Assassination Hearings - Dr. Vincent P. Guinn (Conclusion)
(17:10:58) Stokes adjourns the hearings (17:11:05) Hearings host SANDFORD UNGAR voices over committee shot to sum up afternoon's testimony of Guinn, shot soon after switches to him and after concluding his summary of the testimony he introduces panel members Professor JACOB COHEN of Brandeis University and DAVID LIFTON Warren Commission critic who give differing opinions about the significance of Guinn's testimony (17:14:10) Ungar closes out the hearing (17:14:33) Shot of almost empty hearing room (17:14:43) PBS funding credit